JP4705556B2 - Wireless microphone transmitter, receiver and system - Google Patents

Description

  The present invention makes it possible to select a sound quality corresponding to a use application in a wireless microphone technology.

2. Description of the Related Art Conventionally, wireless microphone transmitters, receivers, and wireless microphone systems that combine these are used in various fields including broadcasting in railway stations. In a wireless microphone system, radio waves from one or more wireless microphone transmitters (hereinafter also simply referred to as “transmitters”) are received by a wireless microphone receiver (hereinafter also simply referred to as “receivers”). There has also been an example in which a transmitter or a receiver is provided with a function of switching or adjusting the level of an audio input level using an ATT (attenuator) (see, for example, Patent Document 1).
JP2002-9640

  However, the optimal sound quality differs depending on the usage of the wireless microphone, that is, the content of the transmitted sound, such as vocals, musical instruments, speech, etc. However, in the conventional example as described above in which only the audio input level can be adjusted, it differs depending on the application. There was a problem that equipment was required and the cost was increased.

  The present invention solves the above-described problems, and an object of the present invention is to make it possible to select a sound quality according to the intended use in the wireless microphone technology.

In order to achieve the above object, according to one aspect of the present invention, in a wireless microphone transmitter, a selection unit that receives selection of sound quality, a microphone for voice input, and an A / D that digitizes voice input by the microphone. A D converter and a coding process for converting the signal digitized by the A / D converter into a digital audio format based on the sound quality selected by the selection means, and using the coded signal for the coding process adding quality information representative of the digital audio format are, possess an encoding processing unit, a radio unit for transmitting the coded signal processed by the encoding processing unit, wherein the selection means, a plurality of sound set in advance The encoding processing means determines the selected one sound quality, and selects a sound quality corresponding to the determined sound quality. Namikkurenji, compressibility, and characterized by selecting a value such that the transmission volume.
In another aspect, the one sound quality is normal, speech, or vocal, and the encoding processing means determines the dynamic range, the compression rate, and the transmission amount when it is determined as normal. If a value set in advance is selected and the speech is determined, the dynamic range lower than the normal, a high compression rate, and a value that results in a small transmission amount are selected, or the vocal is determined. In such a case, the dynamic range, the compression rate, and the value that provides a large transmission amount are selected.

Another aspect of the present invention is a wireless unit that receives and demodulates a signal in a wireless microphone receiver, and information that accompanies the signal based on the signal demodulated by the wireless unit. Extracting sound quality information representing a digital audio format and decoding the digital audio signal according to a digital audio format determined based on the sound quality information, and decoding the digital audio signal decoded by the decode processing unit possess a D / a converter to restore the analog audio signal, wherein the digital audio format is one of quality of a plurality of sound that is set in advance, said decoding processing means, said one quality Judgment is performed, and processing is performed with a dynamic range, a compression rate, and a transmission amount corresponding to the determined sound quality .
In another aspect, the one sound quality is one of normal, speech, and vocal, and the decoding processing unit determines the dynamic range, the compression rate, and the transmission amount when it is determined as the normal. If it is determined that the speech is set in advance, it is processed with a dynamic range lower than the normal, a high compression rate, and a small transmission amount, or when the vocal is determined, the normal It is characterized by processing with a higher dynamic range, a lower compression ratio, and a larger transmission amount.

  Another aspect of the present invention is a wireless microphone system further comprising the above wireless microphone transmitter and the above wireless microphone receiver.

  According to the present invention as described above, it is possible to arbitrarily select and switch the sound quality, so that it is not necessary to prepare a wireless microphone system, a transmitter and a receiver with different standards for each usage, A single system can easily cope with any application, and wasteful costs and equipment can be reduced.

  Next, the best mode for carrying out the present invention will be described with reference to the drawings. It should be noted that assumptions common to those already described in the background art and problems are omitted as appropriate.

[1. Constitution〕
In the present embodiment, a wireless microphone transmitter configured as shown in FIG. 1 (hereinafter also simply referred to as “transmitter”) and a wireless microphone receiver configured as illustrated in FIG. 2 (hereinafter also simply referred to as “receiver”). ) And a wireless microphone system (hereinafter also referred to as “the present system”), and can be grasped as a method corresponding to each of the transmitter, the receiver, and the present system.

[1-1. (Configuration of transmitter)
First, as shown in FIG. 1, the transmitter includes a microphone (microphone) 1 for voice input, an amplifier 2 for a signal from the microphone 1, and a voice processing unit 30 that performs processing such as digitization on the voice signal. And a transmission processing unit 50 that performs processing for transmission on the processed audio signal, a transmission unit S, and a liquid crystal operation unit 90.

  Among these, the audio processing unit 30 includes an A / D conversion unit 3 that is an A / D converter that is realized by a DSP and digitizes audio input by the microphone 1, and an audio codec 4. This is a part for adjusting the number of quantization bits, adjusting the sampling rate, adjusting the CODEC (codec), etc., using a DSP or the like.

  The transmission processing unit 50 includes an error correction unit 5, a channel codec 6, and a baseband processing unit 7, and is a part that adjusts the number of error correction check symbols, adjusts the transmission band, and the like.

  The liquid crystal operation unit 90 includes a control unit 9 such as a CPU, an operation unit 10 such as switches, and a display unit 11 such as a liquid crystal panel, and a selection unit that accepts selection of sound quality in transmission from the user. Realized.

  The control unit 9 is a part that performs processing related to sound quality information (sound quality information) representing the format of digital audio to be transmitted in addition to control of each unit, and sends a sound signal together with the sound processing unit 30 and the transmission processing unit 50. Realize the encoding processing means to process to credit. The transmission unit S is a radio unit that transmits the signal encoded by the encoding processing unit using an antenna.

[1-2. Receiver configuration)
On the other hand, as shown in FIG. 2, the receiver includes a receiving unit R that is a radio unit that receives and demodulates a signal from the transmitter with an antenna, a transmission processing unit 20, an audio processing unit 40, and a liquid crystal display unit 80. And an amplifier 16 and a speaker 17 which are audio output units for outputting the decoded audio.

  Among these, the transmission processing unit 20 is realized by a DSP or the like, and is paired with a configuration (baseband processing unit 12, channel codec 13, error correction unit 25) that is paired with the transmission processing unit 50 of the transmitter. It is a part corresponding to processing. The voice processing unit 40 is a part corresponding to a paired configuration (voice codec 14, D / A conversion unit 15) and a paired process with respect to the voice processing unit 30 of the transmitter.

  The transmission processing unit 20 and the audio processing unit 40 together with the control unit 18 realize a decoding processing means for decoding a digital audio signal from the demodulated signal, and the D / A conversion unit 15 This is a D / A converter that restores the digital audio signal decoded in (1) to an analog audio signal.

[2. Action)
The present embodiment configured as described above operates as follows.
[2-1. (Action of transmitter)
First, as an operation procedure of the transmitter, as shown in the flowchart of FIG. 3, by using a liquid crystal operation unit 90 from a user of the transmitter, for example, by selecting a voice, speech, or the like from a sound quality menu. Then, selection of sound quality suited to the intended use, that is, digital audio format is accepted (step S11).

  Then, the encoding processing means of the transmitter (that is, when the control unit 9 controls the audio processing unit 30 and the transmission processing unit 50), the signal digitized by the A / D conversion unit 3 is converted by the liquid crystal operation unit 90. Transmission processing for transmission is obtained by performing a coding process for conversion into a digital audio format (for example, sampling frequency, number of quantization bits, compression method) based on the selected sound quality.

  At this time, the sound quality setting instruction (step S12) by the control unit 9, that is, the digital sound format is switched (steps S14 to S14) in accordance with the selected sound quality such as normal, speech, or vocal (step S13). S16, steps S17 to S19, or steps S20 to S22), and the transmission information obtained as a result is passed to the radio unit (transmitting unit S).

  At this time, the dynamic range and compression ratio (for example, steps S17 and S18) are controlled mainly by the audio codec 4 in the audio processing unit 30 such as a DSP by adjusting the number of quantization bits, the sampling rate, the CODEC, and the like. The transmission amount (for example, step S19) is controlled mainly by the channel codec 6 of the transmission processing unit 50 by adjusting the number of error correction check symbols and the transmission band.

  In addition, the control unit 9 adds sound quality information (voice quality information) representing the digital voice format used for the encoded signal to the transmission information converted into the digital voice format in the form of control information or the like. It adds (step S12. Encoding process).

[2-2. (Receiver action)
On the other hand, the operation procedure of the decoding processing means (transmission processing unit 20, audio processing unit 40, control unit 18) on the receiver side is shown in the flowchart of FIG. In other words, the decoding processing means first determines the transmission information received in the form of control information or the like based on the signal received and demodulated by the receiving unit R, that is, transmission information (step S51). The sound quality information (sound quality information) representing the digital sound format is extracted (step S52).

  The digital audio format that is automatically determined based on the audio information, that is, the sound quality (step S53), according to the sound quality, that is, the digital audio format (steps S54 to 56, steps S57 to 59, or steps S60 to S62) The audio signal is decoded (decoding process), converted into an analog signal by the D / A converter 15, and passed to the amplifier 16 and the speaker 17 serving as the audio output unit.

  At this time, the transmission amount (eg, step S57) is controlled mainly by the channel codec 13 of the transmission processing unit 20 by adjusting the number of error correction check symbols and the transmission band. Further, the compression rate and dynamic range (for example, steps S58 and S59) are controlled mainly by adjustment of the number of quantization bits, sampling rate, CODEC, and the like by the channel codec 6 in the audio processing unit 40 such as a DSP.

[3. effect〕
As described above, according to the present embodiment, it is possible to arbitrarily select and switch the audio quality, and to prepare a wireless microphone system, a transmitter, and a receiver with different standards for each usage. In addition, since one system can easily cope with any usage, wasteful costs and facilities can be reduced.

[4. Other embodiments]
In addition, this invention is not limited to the said embodiment, The thing illustrated below and other embodiment other than that are included. As an example, the above description is merely an example, and choices and combinations such as a sampling frequency, the number of quantization bits, and a compression method are free. For example, in addition to normal, vocal, and speech, the sound quality is different for musical instruments. Needless to say, the present invention can be appropriately modified by using a digital audio format (for example, steps S24 to S26 in FIG. 3), and such modifications are also within the scope of the present invention.

The figure which illustrates the structure of the transmitter in embodiment of this invention. The figure which illustrates the structure of the receiver in embodiment of this invention. The flowchart which illustrates the operation | movement procedure of the transmitter in embodiment of this invention. The flowchart which illustrates operation | movement of the receiver in embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Microphone 2 ... Amplifier 3 ... A / D conversion part 4,14 ... Voice codec 5,25 ... Apology correction part 6,13 ... Channel codec 7,12 ... Baseband process part 9,18 ... Control part 10 ... Operation part DESCRIPTION OF SYMBOLS 11, 19 ... Display part 15 ... D / A conversion part 16 ... Amplifier 17 ... Speaker 20, 50 ... Transmission processing part 30, 40 ... Sound processing part 80 ... Liquid crystal display part 90 ... Liquid crystal operation part R ... Reception part S ... Transmission Part

Claims (5)

Selection means for accepting selection of sound quality;
A microphone for voice input,
An A / D converter for digitizing sound input by the microphone;
The digital audio format used for the encoded signal that is subjected to encoding processing for converting the signal digitized by the A / D converter into a digital audio format based on the sound quality selected by the selection means Encoding processing means for adding sound quality information representing
A wireless unit that transmits a signal encoded by the encoding processing unit;
I have a,
The selection means selects one sound quality from a plurality of preset sound qualities,
The encoding processing means determines the selected one sound quality, and selects a value corresponding to a dynamic range, a compression rate, and a transmission amount corresponding to the determined sound quality. Machine. The one sound quality is normal, speech, or vocal,
  The encoding processing unit selects a preset value for a dynamic range, a compression rate, and a transmission amount when the normal is determined, and a dynamic range lower than the normal when the speech is determined. Select a value that results in a high compression rate and a small transmission amount, or, when determined as the vocal, a value that results in a dynamic range higher than the normal, a low compression rate, and a large transmission amount. The wireless microphone transmitter according to claim 1, wherein the wireless microphone transmitter is selected. A radio unit for receiving and demodulating the signal;
Based on the signal demodulated by the radio unit, information associated with the signal, and the sound quality information representing the digital sound format in the signal is extracted, and the digital sound format is determined based on the sound quality information. Decoding processing means for decoding the signal;
A D / A converter for restoring the digital audio signal decoded by the decoding processing means into an analog audio signal;
I have a,
The digital audio format is one of a plurality of preset sound qualities,
The wireless microphone receiver , wherein the decoding processing means determines the one sound quality and performs processing with a dynamic range, a compression rate, and a transmission amount corresponding to the determined sound quality . The one sound quality is normal, speech, or vocal,
When the decoding processing means determines that the normal, the dynamic range, compression rate, and transmission amount are set in advance, and when the speech is determined, the dynamic range lower than the normal, 4. The processing according to claim 3, wherein processing is performed with a high compression rate and a small transmission amount, or processing is performed with a dynamic range higher than the normal, a low compression rate, and a large transmission amount when the vocal is determined. The listed wireless microphone receiver. A wireless microphone transmitter according to claim 1 or 2 ,
A wireless microphone receiver according to claim 3 or claim 4 ,
A wireless microphone system comprising:

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